Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=299a3be0d3d02e967... Commit: 299a3be0d3d02e96794bb2c36217955c2b03f049 Parent: bf73ccb8483219c72cb7e80daf2e40f0a14db4e1 Author: David Teigland teigland@redhat.com AuthorDate: Wed Apr 29 10:00:38 2015 -0500 Committer: David Teigland teigland@redhat.com CommitterDate: Wed Apr 29 16:27:40 2015 -0500

man: lvmthin section about use-policies

--- man/lvmthin.7.in | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 116 insertions(+), 2 deletions(-)

diff --git a/man/lvmthin.7.in b/man/lvmthin.7.in index dab2d7e..79ca40a 100644 --- a/man/lvmthin.7.in +++ b/man/lvmthin.7.in @@ -254,6 +254,8 @@ or vgchange to activate thin snapshots with the "k" attribute. .br .B Metadata space exhaustion .br +.B Automatic extend settings +.br .B Zeroing .br .B Discard @@ -834,7 +836,8 @@ extended. (Disabling dmeventd is not recommended.) .IP [bu] Automatic extension of the thin pool is too slow given the rate of writes to thin LVs in the pool. (This can be addressed by tuning the -thin_pool_autoextend_threshold and thin_pool_autoextend_percent.) +thin_pool_autoextend_threshold and thin_pool_autoextend_percent. +See "Automatic extend settings".)

.IP [bu] The VG does not have enough free blocks to extend the thin pool. @@ -877,6 +880,117 @@ repair. 4. Check and repair file system with fsck.

+.SS Automatic extend settings + +& + +Thin pool LVs can be extended according to preset values. The presets +determine if the LV should be extended based on how full it is, and if so +by how much. When dmeventd monitors thin pool LVs, it uses lvextend with +these presets. (See "Automatically extend thin pool LV".) + +Command to extend a thin pool data LV using presets: +.br +.B lvextend --use-policies VG/ThinPoolLV + +The command uses these settings: + +.BR lvm.conf (5) +.B thin_pool_autoextend_threshold +.br +autoextend the LV when its usage exceeds this percent. + +.BR lvm.conf (5) +.B thin_pool_autoextend_percent +.br +autoextend the LV by this much additional space. + +To see the default values of these settings, run: + +.B lvmconfig --type default --withcomment +.RS +.B activation/thin_pool_autoextend_threshold +.RE + +.B lvmconfig --type default --withcomment +.RS +.B activation/thin_pool_autoextend_percent +.RE + +To change these values globally, edit +.BR lvm.conf (5). + +To change these values on a per-VG or per-LV basis, attach a "profile" to +the VG or LV. A profile is a collection of config settings, saved in a +local text file (using the lvm.conf format). lvm looks for profiles in +the profile_dir directory, e.g. /etc/lvm/profile/. Once attached to a VG +or LV, lvm will process the VG or LV using the settings from the attached +profile. A profile is named and referenced by its file name. + +To use a profile to customize the lvextend settings for an LV: + +.IP [bu] 2 +Create a file containing settings, saved in profile_dir. +For the profile_dir location, run: +.br +.B lvmconfig config/profile_dir + +.IP [bu] 2 +Attach the profile to an LV, using the command: +.br +.B lvchange --metadataprofile ProfileName VG/ThinPoolLV + +.IP [bu] 2 +Extend the LV using the profile settings: +.br +.B lvextend --use-policies VG/ThinPoolLV + +.P + +.I Example +.br +.nf +# lvmconfig config/profile_dir +profile_dir="/etc/lvm/profile" + +# cat /etc/lvm/profile/pool0extend.profile +activation { + thin_pool_autoextend_threshold=50 + thin_pool_autoextend_percent=10 +} + +# lvchange --metadataprofile pool0extend vg/pool0 + +# lvextend --use-policies vg/pool0 +.fi + +.I Notes +.IP [bu] 2 +A profile is attached to a VG or LV by name, where the name references a +local file in profile_dir. If the VG is moved to another machine, the +file with the profile also needs to be moved. + +.IP [bu] 2 +Only certain settings can be used in a VG or LV profile, see: +.br +.B lvmconfig --type profilable-metadata. + +.IP [bu] 2 +An LV without a profile of its own will inherit the VG profile. + +.IP [bu] 2 +Remove a profile from an LV using the command: +.br +.B lvchange --detachprofile VG/ThinPoolLV. + +.IP [bu] 2 +Commands can also have profiles applied to them. The settings that can be +applied to a command are different than the settings that can be applied +to a VG or LV. See lvmconfig --type profilable-command. To apply a +profile to a command, write a profile, save it in the profile directory, +and run the command using the option: --commandprofile ProfileName. + + .SS Zeroing

& @@ -1242,10 +1356,10 @@ skipped while mounting readonly:

mount /dev/VG/SnapLV /mnt -o ro,nouuid,norecovery

- .SH SEE ALSO .BR lvm (8), .BR lvm.conf (5), +.BR lvmconfig (8), .BR lvcreate (8), .BR lvconvert (8), .BR lvchange (8),